No CPU / MCU led pulse-fade

Step 5 Questions!

Since I am adding this step before anyone sees it, this may be updated later on, but for now

1) what if I want to use a higher voltage (ie 12V)?
use an appropriate resistor for your led, and make sure your capacitor is rated for at least the voltage applied + ~10% or more, I am actually using a 25v cap even though I specified 10V+

jochem says:
when running this on more than 5V, you'll need to increase the value of R3, or your cap will be grounded all the time. I ended up using a 47KOhm resistor, instead of the 10KOhm one listed here (other parts the same).

2) what if I want to slow down the fade in time?
use a higher value resistor for R1 or use a  larger farad value capacitor

3) what if I want to slow down the fade out time?
use a higher value resistor for R3 or a larger farad value capacitor

4) what if I want to speed up either?
fade in time is pretty close to instant with R1 at 1k  so your not going to have a lot of play room, fade out time does have a little bit more wiggle room but results will vary,  of course you could also use a smaller cap


Okay, that is all I can think of at this moment, have fun and play around, see what you can do with it and figure out why its happening...

Till next time!

~ Osgeld ~

Comments

[crazyg]

thanks for doing this,my leccy theroy depends a fair bit on what i remember from school 15-16 yrs ago(couple of theroy lessons and two weeks of sanding a perspex box) ,i mostly guess stuff (dragging a live wire accross a board untill something happens) which keeping it low tek (with kits n such) gets me through,hopefully ill be able to make some use of a load of caps iv pulled from things,recently tried to make a cd player focus thingy oscilate with caps (no transistor fail!)other diagrams on t'net were a bit to algebra based to be enjoyable,so i did the stick bits together routine and see what happens, Nice diagrams they will be handy references when i forget what im doing,nice led by the way.